The famous Jouchi Temple (浄智寺) in Kamakura has one of my favorite stairs. The temple itself dates back to 1283 but the original stairs were destroyed in the 1923 earthquake. How to recreate the ancient atmosphere of a worn old stone stair? 
The solution was to use the local tuff sandstone, usually too soft to be considered for stairs, but in just 97 years the softer parts of this irregular variety of stone ihas worn out to the point it looks like it has been there longer than the temple itself even.
The stone is called Kamakura-Ishi, and since quarrying it has been long banned (to preserve the natural landscape of the area), it is now known as "Diamond Stone" because of its rarity: its use is mandated in the conservation of many historically important buildings and gardens.
Whenever an old stone building is taken down or some ancient foundation stone turns up in archaeological excavations, it is carefully removed and stored for future use. The softness of this local tuff stone is a vital ingredient in the magic of the city's ancient temples.
